Determination of the orientation in small areas of the exit wave

Local differences in thickness and misorientation in a through-focus recons tructed exit wave hamper direct interpretation. These local thicknesses and misorientations can be refined on an atomic scale using the intensities of the Fourier components with the refinement procedure in which a least-squa res refinement is combined with a multi-slice calculation, The method was a pplied to the superconductor La3Ni2B2N3 The crystal tilt and specimen thick ness can be determined with an R-value of 8-25%, with a better R-value for thinner areas. Significant differences in the refined tilts, thicknesses an d R-values are observed when reconstructed exit waves that are corrected fo r mechanical vibration are compared with reconstructed exit waves, which ar e uncorrected. (C) 2001 Elsevier Science B.V. All rights reserved.